The present invention relates to the structure of power connectors which carry electric current from a power source on one module, thru passed joints with the connector, to the power input terminal in an integrated circuit chip (IC-chip) on another module.
Throughout the history of the IC-chip industry, the number of transistors which have been integrated into a single IC-chip has steadily increased; and consequently, the amount of current which is needed to supply power to the IC-chip has also steadily increased. Today, a typical CMOS microprocessor IC-chip requires a power source which can supply about fifty amps; and, the projections are that in a few years, a typical microprocessor IC-chip will require a power source which can supply about one-hundred-fifty amps.
In the prior art, a common practice is to attach the IC-chip to one module and send electrical power to the IC-chip from a power source which is on another separate module. This is done, for example, in test equipment which sequentially tests a large number of IC-chips that are mass produced. There a printed circuit board is provided which holds several of the IC-chips that are to be tested; and this printed circuit board is sequentially connected and disconnected to the test equipment thru a power connector and a signal connector. The power connector carries current from a power source to the IC-chips on the printed circuit board while the signal connector carries test signals to and from those IC-chips.
Conventionally, the power connector is a xe2x80x9cpin and socketxe2x80x9d type of connector. In this type of connector, the xe2x80x9cpinxe2x80x9d is a solid metal cylinder with a typical length of about one inch and a typical diameter of about one-half inch; and, the xe2x80x9csocketxe2x80x9d is a metal member that has cylindrical shaped hole into which the pin snugly fits.
However, a problem with the pin and socket type of connector is that each time a connection is to be made, the pin must be perfectly aligned with the hole in the socket. If the pin is out of line with the socket hole, then the pin will hit the socket when they are moved together; and damage to the connector and/or the two modules can occur. This damage can be quite extensive where the two modules are moved together automatically by mechanism which are motor driven. To avoid such damage, various alignment mechanisms can be employed; however, any alignment mechanism adds to the cost of the overall system.
Also in the prior art, a xe2x80x9cfuzz buttonxe2x80x9d type of connector has been disclosed which avoids the alignment problem of the pin and socket type of connector. A fuzz button consists of a thin strand of wire which has been wadded up into the shape of a button. In a fuzz button type of connector, the fuzz button is held in a hole on a flat surface of the connector, and a portion of the fuzz button protrudes from the hole past the flat surface. This connector is attached to one module; a flat metal contact pad is provided on the other module; and a connection is made between the two modules by pressing the portion of the fuzz button which protrudes from the hole against the flat contact pad. Here, the fuzz button need not be perfectly aligned with the contact pad.
However, one problem with the fuzz button type of connector is that the hole which holds the fuzz button must always be kept in an upright position. Otherwise, the fuzz button can fall out of the hole and thereby make the connector inoperable. Thus the fuzz button is not suitable for use in a printed circuit board which holds several IC-chips that are to be tested, and which is manually handled with various orientations as it is repeatedly connected and disconnected to the test equipment.
Also, another problem with the fuzz button is that its thin strand of wire has a current carrying capacity of only about one amp. Thus, to carry fifty to one-hundred fifty amps of current to the power input of an IC-chip, a connector which holds a large number of fuzz buttons should be required. However, that presents a reliability problem because as the number of fuzz buttons in a connector increases, the probability of one or more fuzz buttons falling out of their respective hole increases.
Accordingly, a primary object of the present invention is to provide a connector for sending current to the power input of an IC-chip by which all of the above described problems are avoided.
In accordance with the present invention, a connector for sending power from a power source on one module to an IC-chip on another module is comprised of: 1) a solid block having a top surface, a bottom surface, and a side with a slot that extends from the top surface to the bottom surface; and 2) a springy strip of metal having a center section which is held by the slot in the block. This springy strip also has a first end section which extends from the center section and includes a springy input contact that is cantilevered above the top surface of the block. Also, the springy strip has a second end section which extends from the center section and includes a springy output contact that is cantilevered below the bottom surface of the block.
To transfer electrical power from the power source thru the connector to the IC-chip, two pressed joints are made. The first pressed joint occurs between the springy input contact on the metal strip and a flat metal power pad which is provided on the module that holds the power source to receive current from that power source. The second pressed joint occurs between the springy output contact on the metal strip and a flat metal power pad which is provided on the module that holds the IC-chip to send current to that IC-chip.
One desirable attribute of the above connector is that a connection is made between the springy input contact and its corresponding power pad even when they are not perfectly aligned. Similarly, a connection is made between the springy output contact and its corresponding power pad even when they are not perfectly aligned. Also, the above connector remains operable in any orientation because the springy strip of metal is held firmly in the slot of the connector block. Further, the above connector is capable of carrying a current of fifty to one-hundred-fifty amps.